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diff --git a/bin/date/date.1 b/bin/date/date.1 new file mode 100644 index 0000000..f15119a --- /dev/null +++ b/bin/date/date.1 @@ -0,0 +1,262 @@ +.\" $NetBSD: date.1,v 1.47 2018/01/27 18:59:38 wiz Exp $ +.\" +.\" Copyright (c) 1980, 1990, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" This code is derived from software contributed to Berkeley by +.\" the Institute of Electrical and Electronics Engineers, Inc. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)date.1 8.3 (Berkeley) 4/28/95 +.\" +.Dd January 25, 2018 +.Dt DATE 1 +.Os +.Sh NAME +.Nm date +.Nd display or set date and time +.Sh SYNOPSIS +.Nm +.Op Fl ajnu +.Op Fl d Ar date +.Op Fl r Ar seconds +.Op Cm + Ns Ar format +.Sm off +.Oo Oo Oo Oo Oo Oo +.Ar CC Oc +.Ar yy Oc +.Ar mm Oc +.Ar dd Oc +.Ar HH Oc Ar MM Oo +.Li \&. Ar SS Oc Oc +.Sm on +.Sh DESCRIPTION +.Nm +displays the current date and time when invoked without arguments. +Providing arguments will format the date and time in a user-defined +way or set the date. +Only the superuser may set the date. +.Pp +The options are as follows: +.Bl -tag -width Ds +.It Fl a +Use +.Xr adjtime 2 +to change the local system time slowly, +maintaining it as a monotonically increasing function. +.Fl a +implies +.Fl n . +.It Fl d Ar date +Parse the provided human-described date and time and display the result without +actually changing the system clock. +(See +.Xr parsedate 3 +for examples.) +.It Fl j +Parse the provided canonical representation of date and time (described below) +and display the result without actually changing the system clock. +.It Fl n +The utility +.Xr timed 8 +is used to synchronize the clocks on groups of machines. +By default, if +.Xr timed 8 +is running, +.Nm +will set the time on all of the machines in the local group. +The +.Fl n +option stops +.Nm +from setting the time for other than the current machine. +.It Fl r Ar seconds +Print out the date and time that is +.Ar seconds +from the Epoch. +.It Fl u +Display or set the date in UTC (universal) time. +.El +.Pp +An operand with a leading plus +.Pq Cm + +sign signals a user-defined format +string which specifies the format in which to display the date and time. +The format string may contain any of the conversion specifications described +in the +.Xr strftime 3 +manual page, as well as any arbitrary text. +A <newline> character is always output after the characters +specified by the format string. +The format string for the default display is: +.Bd -literal -offset indent +%a %b %e %H:%M:%S %Z %Y +.Ed +.Pp +If an operand does not have a leading plus sign, it is interpreted as +a value for setting the system's notion of the current date and time. +The canonical representation for setting the date and time is: +.Pp +.Bl -tag -width Ds -compact -offset indent +.It Ar CC +The first two digits of the year (the century). +.It Ar yy +The second two digits of the year. +If +.Ar yy +is specified, but +.Ar CC +is not, a value for +.Ar yy +between 69 and 99 results in a +.Ar CC +value of 19. +Otherwise, a +.Ar CC +value of 20 is used. +.It Ar mm +The month of the year, from 01 to 12. +.It Ar dd +The day of the month, from 01 to 31. +.It Ar HH +The hour of the day, from 00 to 23. +.It Ar MM +The minute of the hour, from 00 to 59. +.It Ar SS +The second of the minute, from 00 to 60. +.El +.Pp +Everything but the minutes is optional. +.Pp +Time changes for Daylight Saving and Standard Time and leap seconds +and years are handled automatically. +.Sh ENVIRONMENT +The following environment variables affect the execution of +.Nm : +.Bl -tag -width iTZ +.It Ev TZ +The timezone to use when displaying dates. +See +.Xr environ 7 +for more information. +.El +.Sh FILES +.Bl -tag -width /usr/share/zoneinfo/posixrules -compact +.It Pa /etc/localtime +Symlink pointing to system's default timezone information file in +.Pa /usr/share/zoneinfo +directory. +.It Pa /usr/lib/locale/<L>/LC_TIME +Description of time locale <L>. +.It Pa /usr/share/zoneinfo +Time zone information directory. +.It Pa /usr/share/zoneinfo/posixrules +Used with POSIX-style TZ's. +.It Pa /usr/share/zoneinfo/GMT +For UTC leap seconds. +.It Pa /var/log/wtmp +A record of date resets and time changes. +.It Pa /var/log/messages +A record of the user setting the time. +.El +.Pp +If +.Pa /usr/share/zoneinfo/GMT +is absent, UTC leap seconds are loaded from +.Pa /usr/share/zoneinfo/posixrules . +.Sh EXAMPLES +The command: +.Bd -literal -offset indent +date '+DATE: %m/%d/%y%nTIME: %H:%M:%S' +.Ed +.Pp +will display: +.Bd -literal -offset indent +DATE: 11/21/87 +TIME: 13:36:16 +.Ed +.Pp +The command: +.Bd -literal -offset indent +date 8506131627 +.Ed +.Pp +sets the date to +.Dq Li "June 13, 1985, 4:27 PM" . +.Pp +The command: +.Bd -literal -offset indent +date 1432 +.Ed +.Pp +sets the time to +.Li "2:32 PM" , +without modifying the date. +.Sh DIAGNOSTICS +Exit status is 0 on success, 1 if unable to set the date, and 2 +if able to set the local date, but unable to set it globally. +.Pp +Occasionally, when +.Xr timed 8 +synchronizes the time on many hosts, the setting of a new time value may +require more than a few seconds. +On these occasions, +.Nm +prints: +.Ql Network time being set . +The message +.Ql Communication error with +.Xr timed 8 +occurs when the communication +between +.Nm +and +.Xr timed 8 +fails. +.Sh SEE ALSO +.Xr adjtime 2 , +.Xr gettimeofday 2 , +.Xr settimeofday 2 , +.Xr parsedate 3 , +.Xr strftime 3 , +.Xr utmp 5 , +.Xr environ 7 , +.Xr timed 8 +.Rs +.%T "TSP: The Time Synchronization Protocol for UNIX 4.3BSD" +.%A R. Gusella +.%A S. Zatti +.Re +.Sh STANDARDS +The +.Nm +utility is expected to be compatible with +.St -p1003.2 . +.Sh HISTORY +A +.Nm +utility appeared in +.At v1 . |